K5PC:
>The manufacturer claims that this set-up will give performance
of a 2-wave-length beverage in a fraction of the space, and that
it will out-perform the K9AY, flags, EWE's and pennants.
For the small loops...true. For Beverages, it depends...
See Table 7-47 of ON4UN's 4th edition (p. 7-97) for summary
metrics of vertical arrays, Beverages and loops.
Why "it depends"? Because it depends on where your
primary noise source comes from. Although both a 4-square
and 2wl Beverage have about the same RDF (omnidirectional S/N
metric), 4-squares get more of their S/N from rejection from
the rear (due to better F/R) while a 2wl Beverage gets more
S/N from the front (due to a narrower forward beamwidth).
ON4UN's metrics (1/4 wl spaced 4-SQ vs 300m Beverage):
Antenna DMF RDF 3dB BW
4-SQ 24.0 11.6 86
300m Bev 21.3 12.9 62
where DMF is ON4UN's F/R metric (Directivity Merit Figure)
...RDF is W8JI's omnidirectional S/N metric
and 3dB BW is the forward beam width (best forward metric)
Thus the 4-SQ would be better when noise is from the rear
180 degrees, but a Beverage would be better when noise
is in the same general direction as the target signal.
At my QTH, where rejecting noise from the SW quadrant
is important when listening NE, I like a pair of end-fire
Beverages (of any length). An EF pair needs only another
~110' in length and 20' in width than a single Beverage,
but has far better F/R (i.e. DMF) than even a 4-SQ.
Antenna DMF RDF 3dB BW
160m Bev 30.1 11.6 69
300m Bev 33.8 13.9 57
>Life would be made simpler for many of us without all those beverages to
maintain.
No question a 4-square array is simpler than having
Beverages in multiple directions, but be careful about that
"will give performance of a 2wl Beverage" statement. That
may depend on what direction your noise usually comes from.
73, Bill W4ZV
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